Re: Display list limitations

I don't understand how this works.
I am texture mapping a quad. Really, just drawing a photo/picture in a
layout tool.
So I should do the glBindTexture outside of the list?
Hmm.

So, I can't easily make a BIG list with many differently textured
objects, like say I have 100 photos I can't put them in ONE list?
Hmm.

Ok.

So lists make sense ONLY for similarly textured objects and just plain
lines and stuff?

On Feb 24, 2004, at 2:57 PM, John Stauffer wrote:

That is probably part of the problem. Display lists copy the texture
into the list, then when you draw with the list the texture is
submitted back into OpenGL. The result of this is an extra copying of
the texture.

I would avoid putting textures is display lists if performance is the
goal.

John

On Feb 24, 2004, at 2:53 PM, Steve Israelson wrote:

Yes it is. (I think)
I open the list, render the textured quad, and close the list.

On Feb 24, 2004, at 1:32 PM, John Stauffer wrote:

Is the texture part of the display list?

John

On Feb 24, 2004, at 1:06 PM, Steve Israelson wrote:

Our app is doing simple UI type layout, like interface builder.
Each texture is usually just a picture, and the geometry is a quad.

I have followed the sample code for making the texture, so I think
it is optimal.
Presumably the texture is always in VRAM. They don't typically
change at all. (think of a button in Interface builder - the image
for the button rarely changes, tho its position does).

On Feb 24, 2004, at 12:57 PM, Geoff Stahl wrote:

How big are your textures. I suspect the glBegin time is the
texture uploads. Look to client storage, and texture range (see
the sample) to adjust the way texture memory is handled.

Is you are drawing, say less than 16 triangles I suspect a display
list is just going to be more overhead. Also, ensure you are not
generating the list multiple times (which I suspect you are not,
but it is worth checking).

Lastly, use the driver monitor to see if you are waiting on the
graphics hardware, depending on complexity the hardware could be
fill rate bound.

On Feb 24, 2004, at 11:51 AM, Steve Israelson wrote:

I have noticed in my code that if I disable the generation and
use of display lists that my drawing speed goes up a lot.
Does anyone know of the guidelines as to when a display list will
slow things down?

What I am doing is merely drawing pictures/photos using textured
quads. Maybe 20 of them all different. All in one list.

Oh, and when profiler says glBegin is taking the most amount of
time, what can you do?

I am only getting 10fps on a G4/500mhz Machine with a plain AGP
Radeon.
The OpenGL viewport is 1000x600

Apple Footer

This site contains user submitted content, comments and opinions and is for informational purposes only. Apple may provide or recommend responses as a possible solution based on the information provided; every potential issue may involve several factors not detailed in the conversations captured in an electronic forum and Apple can therefore provide no guarantee as to the efficacy of any proposed solutions on the community forums. Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or related to your use of the site. All postings and use of the content on this site are subject to the Apple Support Communities Terms of Use.
Apple